The Rochester mine and associated heap leach facilities is an open pit silver and gold mine located in Pershing County, Nevada approximately 25 miles northeast of the town of Lovelock. The Company owns 100% of the Rochester mine through the Company’s wholly-owned subsidiary, Coeur Rochester, Inc. The mine consists of the main Rochester deposit and the adjacent Nevada Packard deposit, due south of Rochester, and the heap leach facilities east of the Rochester deposit.
Silver and gold mineralization at Rochester is hosted in folded and faulted volcanic rocks of the Triassic-aged Rochester, and overlying Weaver, formations. Silver and gold, consisting of silver sulfosalt minerals, argentite, silver-bearing tetrahedrite and minor native gold are contained in zones of multiple quartz veins and veinlets (vein and vein swarms and stockworks) with variable amounts of pyrite.
The Company spent $3.9 million in exploration at Rochester in 2012, resulting in significant increases in reserves and measured and indicated resources at year-end 2012. The Company completed 138,121 feet (42,099 meters) of reverse circulation, Sonic® (rotary vibratory drilling) and core drilling at the Rochester North and West historic stockpiles, and Northwest Rochester, Nevada Packard and South Mystic areas in 2012. The Company has allocated $3.5 million for exploration at the Rochester property in 2013.
Drilling on just two of six historic stockpiles was successful in defining new mineral resources and mineral reserves at Rochester. Drilling will continue on these and the other stockpiles in 2013.